Compound and Complex Sentences

Background Information:

A clause is a group of words within a sentence that includes a subject and a verb. A phrase is a group of related words within a sentence that does not have both a subject and a verb. Embedding is when a phrase or sentence becomes part of another sentence, serving key grammatical functions (Owens, pg 329).

Clauses and phrases are the most advanced method of language sophistication known to man. With them, a sentence can theoretically be made to communicate anything that can be thought (Pinker, 1995). The existence of clauses and phrases manages to both greatly enrich our communication possibilities while often making effective communication more difficult. Expanded sentences are commonly understood as those which include additional information, such as modifiers or negation, but are not as sophisticated as sentences with clauses or phrases.

Because complexity is increased by adding words within and near clauses and phrases, and because of the difficulty in comparing order of acquisition across categories (e.g. negatives, pronouns, etc.), clause and phrase hierarchies should be manipulated based on the individual needs of the student. A student with difficulty understanding negatives should work on clauses and phrases that include negatives.

We call clauses that are missing words elliptical clauses. For example, “The boy I met was named Fred.” instead of “The boy that I met was named Fred.” Elliptical clauses are common, and especially in oral speech, are often easier to understand. Compound and complex sentences occur when sentences combine independent and/or dependent clauses. Complex sentences are often used to show that one idea takes precedence over another. Compound sentences are often used to show that two ideas are of equal importance. While nearly all assessments contain directions with at least some clauses and phrases, the PLS, CASL, CELF, and OWLS are among the assessments that directly assess production of these structures.

Love the hierarchy model! However, “after school” is a prepositional phrase, not a dependent clause. A phrase does not build complexity into the sentence structure. The example “She opened her backpack after school” is a simple sentence. Phrases do not create complex sentences. In order to be complex, the sentence must contain at least one dependent clause and an independent clause.